A meta-analysis of deep brain structural shape and asymmetry abnormalities in 2,833 individuals with schizophrenia compared with 3,929 healthy volunteers via the ENIGMA Consortium

Schizophrenia is associated with widespread alterations in subcortical brain structure. While analytic methods have enabled more detailed morphometric characterization, findings are often equivocal. In this meta-analysis, we employed the harmonized ENIGMA shape analysis protocols to collaboratively investigate subcortical brain structure shape differences between individuals with schizophrenia and healthy control participants. The study analyzed data from 2,833 individuals with schizophrenia and 3,929 healthy control participants contributed by 21 worldwide research groups participating in the ENIGMA Schizophrenia Working Group. Harmonized shape analysis protocols were applied to each site's data independently for bilateral hippocampus, amygdala, caudate, accumbens, putamen, pallidum, and thalamus obtained from T1-weighted structural MRI scans. Mass univariate meta-analyses revealed more-concave-than-convex shape differences in the hippocampus, amygdala, accumbens, and thalamus in individuals with schizophrenia compared with control participants, more-convex-than-concave shape differences in the putamen and pallidum, and both concave and convex shape differences in the caudate. Patterns of exaggerated asymmetry were observed across the hippocampus, amygdala, and thalamus in individuals with schizophrenia compared to control participants, while diminished asymmetry encompassed ventral striatum and ventral and dorsal thalamus. Our analyses also revealed that higher chlorpromazine dose equivalents and increased positive symptom levels were associated with patterns of contiguous convex shape differences across multiple subcortical structures. Findings from our shape meta-analysis suggest that common neurobiological mechanisms may contribute to gray matter reduction across multiple subcortical regions, thus enhancing our understanding of the nature of network disorganization in schizophrenia.

Increased power by harmonizing structural MRI site differences with the ComBat batch adjustment method in ENIGMA

A common limitation of neuroimaging studies is their small sample sizes. To overcome this hurdle, the Enhancing Neuro Imaging Genetics through Meta-Analysis (ENIGMA) Consortium combines neuroimaging data from many institutions worldwide. However, this introduces heterogeneity due to different scanning devices and sequences. ENIGMA projects commonly address this heterogeneity with random-effects meta-analysis or mixed-effects mega-analysis. Here we tested whether the batch adjustment method, ComBat, can further reduce site-related heterogeneity and thus increase statistical power. We conducted random-effects meta-analyses, mixed-effects mega-analyses and ComBat mega-analyses to compare cortical thickness, surface area and subcortical volumes between 2897 individuals with a diagnosis of schizophrenia and 3141 healthy controls from 33 sites. Specifically, we compared the imaging data between individuals with schizophrenia and healthy controls, covarying for age and sex. The use of ComBat substantially increased the statistical significance of the findings as compared to random-effects meta-analyses. The findings were more similar when comparing ComBat with mixed-effects mega-analysis, although ComBat still slightly increased the statistical significance. ComBat also showed increased statistical power when we repeated the analyses with fewer sites. Results were nearly identical when we applied the ComBat harmonization separately for cortical thickness, cortical surface area and subcortical volumes. Therefore, we recommend applying the ComBat function to attenuate potential effects of site in ENIGMA projects and other multi-site structural imaging work. We provide easy-to-use functions in R that work even if imaging data are partially missing in some brain regions, and they can be trained with one data set and then applied to another (a requirement for some analyses such as machine learning).

Islet cell function in long-term surviving primates after segmental pancreatic allotransplantation

Islet cell function was studied in pancreatectomized primates with functioning segmental pancreatic allografts more than 100 days after transplantation. Segmental allograft recipients were immunosuppressed with total lymphoid irradiation (TL1) and cyclosporine (CSA). After 100 days, islet function was assessed, at which stage immunosuppression was terminated. Glucose, insulin, glucagon, and C-peptide response was assessed during intravenous glucose tolerance test (IVGTT) and during arginine and tolbutamide stimulation. In eight normoglycaemic primates in which immunosuppressive treatment had been stopped and with mean graft survival of 145 days, islet stimulation was associated with moderate glucose intolerance, reduced K-values, hypoinsulinaemia, and low C-peptide values. Postmortem findings in all animals intentionally killed revealed severe graft atrophy in the absence of significant rejection. Severe graft atrophy in normoglycaemic primates, together with significantly impaired graft function after segmental pancreatic transplantation compared to normal animals, suggest that transplantation of the whole pancreas may be mandatory if normal or near-normal function is to be achieved.

Endocrine function after hetero- and ortho-topic segmental pancreatic transplantation in primates

This study assessed the early postoperative pancreatic endocrine function after intraperitoneal segmental hetero- and ortho-topic pancreatic allotransplantation in hemipancreatectomized, nonimmunesuppressed chacma baboons. Hemipancreatectomized animals remained normoglycaemic but rendered significantly reduced K values and insulin release during IVGTT, findings consistent with major pancreatic resection. Segmental hetero- or ortho-topic pancreatic transplantation did not improve reduced K values and hypoinsulinaemia following hemipancreatectomy although orthotopically sited grafts rendered the best glucose tolerance test curves. Glucagon output during IVGTT remained the same in both transplant models. It is concluded that the postoperative hormonal response was similar in both orthotopic and heterotopic transplant recipients, which indicates that drainage of graft venous effluent into the portal circulation has no advantage over systemic insulin drainage as reflected in this "diabetic" model.

Effect of cyclosporine and irradiation on experimental pancreatic allografts in the primate

The present study assessed the effectiveness of cyclosporine (CSA) and subtotal marrow irradiation (TL1) alone, and CSA in combination with TL1 in a primate segmental pancreatic allotransplantation model. Continuous administration of CSA 25 mg/kg/day and 50 mg/kg/day resulted in mean graft survival of 21.5 days and 24.5 days, respectively. Administration of fractionated TL1 800 rad (8 Gy) and 1,000 rad (10 Gy) alone resulted in mean graft survival of 13.3 days and 14.5 days, respectively. Of 20 animals that received TL1 1,000 rad (10 Gy) and CSA 25 mg/kg/day orally for 5 days then 10 mg/kg/day intramuscularly indefinitely, 3 had graft survival of greater than 100 days. Likewise, of a group of 15 animals that received TL1 800 rad (8 Gy) and combined indefinite administration of CSA, 6 had graft survival of greater than 100 days. Although CSA and TL1 administration alone produced modest pancreatic allograft survival, a combination of IL1 (800 or 1,000 rad) and CSA resulted in highly significant segmental pancreatic allograft survival in the primate.

Primate endocrine function after pancreatico-duodenal-splenic allotransplantation

In this study the endocrine function following intraperitoneal hetero- and orthotopic pancreatico-duodenal-splenic allotransplantation (PDS) in hemipancreatectomized, non-immune-suppressed chacma baboons was assessed. Significantly reduced K-values and insulin release together with glucose intolerance during IVGTT were observed in hemipancreatectomized recipients (HPS) without grafts. Orthotopic and heterotopic PDS transplantation improved the glucose intolerance of HPS recipients; orthotopically sited grafts rendering the best curves. Normal glucose tolerance was not achieved. Both orthotopic and heterotopic PDS transplantation rendered suboptimal insulin release during IVGTT; heterotopically draining grafts released significantly more insulin than orthotopic grafts. Hyperglucagonaemia during IVGTT was a constant feature in both groups, heterotopic grafts releasing the most glucagon during stimulation. C-peptide release was significantly lower in orthotopic grafts compared to normal animals or heterotopically drained insulin. It is concluded that glucose tolerance was not directly related to insulin or glucagon release in this study as orthotopic grafts rendered near-normal IVGTT curves in the presence of hypoinsulinaemia, hyperglucagonaemia, and reduced C-peptide values. The hormonal response after PDS transplantation was variable and the advantages of portal vs systemic insulin drainage remain to be defined.

Prolongation of segmental and pancreaticoduodenal allografts in the primate with total-lymphoid irradiation and cyclosporine

The prolongation of segmental and pancreaticoduodenal allografts (PDA) by total lymphoid irradiation (TLI) and in combination with cyclosporine (CsA) was assessed in a well established total pancreatectomy, diabetic, primate transplantation model. Pancreatic transplantation was performed in 119 pancreatectomized baboons (Papio ursinus). Of a total of 109 allografts performed, 71 were segmental allografts (open duct drainage) and 38 PDA. Of 119 graft recipients, 10 received segmental pancreatic autografts. TLI and CsA administered separately to segmental allograft recipients resulted in modest allograft survival and indefinite graft survival was not observed. 8 of 17 (47%) segmental allograft recipients that received TLI and CsA had graft survival beyond 100 days, indicating highly significant pancreatic allograft survival. All long-term segmental allograft recipients were rendered normoglycemic (plasma glucose less than 8 mmol/L) by this immunosuppressive regimen. In contrast, poor results were observed in PDA recipients treated with TLI and CsA. Mean survival in 18 treated PDA recipients was 23.8 days, 8 survived longer than 20 days (44.4%), and 1 greater than 100 days (5.5%). Despite treatment, early rejection of the duodenum in PDA recipients frequently resulted in necrosis and perforation and contributed to a high morbidity and mortality. This study indicates that, in contrast to the significant prolongation of segmental allografts by TLI and CsA, poor immunosuppression was achieved by this regimen in PDA recipients and was associated with a high morbidity and mortality caused by early rejection of the duodenum.

Diabetes in pancreatectomized baboons: a model for pancreatic transplantation studies

This study was designed to assess plasma glucose levels (PLG) and insulin release in totally pancreatectomized baboons when challenged with intravenous glucose administration (IVGTT). Ten animals (Papio ursinus) were used and duodenectomy was intentionally avoided. The PLG at death was 18.0 +/- mmol/L, and the mean K-value within 3 days after pancreatectomy was 0.4% +/- 0.2%, indicating a significant impairment of glucose disappearance from the blood when compared to the control animals (P less than 0.01). Plasma insulin levels before and after stimulation with glucose were below the lowest level of insulin assay sensitivity. We conclude that in the primate, as in the dog, surgical pancreatectomy produced a reliable diabetic model, which is uniformly lethal if left untreated.

Early postoperative pancreatic endocrine function after segmental and pancreaticoduodenal allotransplantation in nonimmunosuppressed primates

In this study we evaluated the short-term hormonal effects of segmental and whole pancreatic allotransplantation on the glucose intolerance produced by hemipancreatectomy in the primate. In hemipancreatectomized animals without grafts the K-values were reduced to 0.6 +/- 0.05, plasma insulin increased from 27.5 +/- 2.5 to 63.5 +/- 6.3 microU/ml, and glucagon levels declined from 252 +/- 29.9 to 216.5 +/- 33.0 pg/ml. Hemipancreatectomized segmental allograft recipients rendered K-values of 0.79 +/- 0.05, plasma insulin increased from 19.98 +/- 3.43 to 66.0 +/- 17.03 microU/ml, and glucagon release declined from 395.6 +/- 63.0 to 226.2 +/- 37.6 pg/ml during IVGTT postoperatively. Hemipancreatectomized, pancreaticoduodenal allograft recipients rendered K-values of 0.82 +/- 0.1, results not significantly different from hemipancreatectomized or segmental allograft recipients. Plasma insulin increased from 29.5 +/- 4.0 to 186.0 +/- 25.0 microU/ml, and glucagon release declined from 1,087.0 +/- 31.6 to 656.0 +/- 12.7 pg/ml. In summary, segmental pancreatic allotransplantation could not, in the short-term, restore the reduced K-values and hypoinsulinaemia in hemipancreatectomized primates to that of normal, unstressed controls. Although K-values of hemipancreatectomized recipients were not significantly improved, whole pancreas transplantation resulted in improved insulin release and hyperglucagonaemia during IVGTT when compared to segmental allograft recipients. The unexpected findings of hypoinsulinaemia and hyperglucagonaemia in both transplant groups may only reflect a function of the stressed state of the animals in the immediate postoperative phase.

The effect of ionizing radiation on the primate pancreas: an endocrine and morphologic study

In this study we evaluated the endocrine, biochemical, and haematological derangements as well as pancreatic and histological changes of the bonemarrow in the primate following external fractionated subtotal marrow irradiation without bonemarrow reconstitution. The irradiation was administered in preparation for pancreatic transplantation. Two groups of animals (ten in each group) received 800 rad (8 Gy) and 1,000 rad (10 Gy) respectively over 4 to 5 weeks. A maximum of 200 rads (2 Gy) were administered weekly as photons from a 6 MV linear accelerator. During irradiation the animals remained normoglycaemic in the presence of transiently elevated liver enzymes and serum amylase values, which returned to normal on completion of the irradiation. Insulin release was significantly reduced in both groups during irradiation and was associated with minimally decreased K-values in the presence of mild glucose intolerance. Pancreatic light morphologic changes included structural changes of both exocrine and endocrine elements and included necrosis of the islet cells and acinar tissue. Islet histology demonstrated striking cytocavitary network changes of alpha and beta cells, including degranulation, vacuolization, mitochondrial destruction, and an increase in lysosomes. A hypoplastic bonemarrow ranging from moderate to severe was observed in all irradiated recipients. Near total fractionated body irradiation in the primate is therefore associated with elevated liver enzymes, pancytopenia, transient hyperamylasaemia, hypoinsulinaemia, a varying degree of pancreatitis, and bonemarrow hypoplasia.

Endocrine function after immunosuppression of pancreatic allograft by ionizing irradiation in the primate

The object of this preliminary study was to evaluate the endocrine function after heterotopic intraperitoneal segmental pancreatic allotransplantation with unligated duct in irradiated, totally pancreatectomized primates. All allograft recipients received, pre- and peroperative donor-specific blood transfusions and peroperative external irradiation from a linear accelerator; 200 rads was administered weekly and increased to a total dose of 1,500 rads. Pancreatic transplantation was performed between 2 and 6 weeks after completion of irradiation and preoperative blood transfusions. As previously reported, only minimal pancreatic allograft survival was achieved following preoperative irradiation. One recipient remained normoglycaemic for greater than 100 days after transplantation, the longest surviving pancreatic allograft recipient reported from this laboratory. Intravenous glucose tolerance test results in this recipient revealed normoglycaemia, reduced K-value, hypoinsulinaemia, normal glucagon response, reduced C-peptide values, and moderate glucose intolerance. Aortography and electron-microscopic examination of allograft biopsy tissue confirmed the presence of a functioning allograft.

Segmental pancreatic allograft survival in baboons treated with combined irradiation and cyclosporine: a preliminary report

The present study was undertaken to evaluate the effectiveness of cyclosporine (CS) alone, total lymphoid irradiation (TLI) alone, and CS in combination with total body irradiation (TBI) in suppressing segmental pancreatic allograft rejection in totally pancreatectomized outbred chacma baboons. The administration of CS 25 mg/kg/day and 50 mg/kg/day resulted in mean graft survival of 21.5 days and 24.5 days, respectively. CS 85 mg/kg/day resulted in median graft survival of 9 days. There was a wide daily fluctuation of CS serum trough levels exhibited between primates receiving the same oral dose. TBI in excess of 300 rads resulted in irreversible bone marrow suppression. Modest results were achieved in recipients of TBI-76 rads (38 X 2 rads), with median graft survival of 21 days, results not different from recipients treated with CS. TLI recipients of 600 rads (150 X 4 rads) resulted in median pancreatic graft survival of 16 days. TBI together with oral CS administration exhibited no synergistic or additive effect and a single peroperative donor-specific blood transfusion did not enhance pancreatic allograft survival in this model. However, of 10 primates receiving TBI 100 rads (50 X 2 rads) and CS 25 mg/kg/day administered orally indefinitely, four remained normoglycemic for more than 60 days. TBI 100 rads (50 X 2 rads) together with oral and parenteral CS resulted in necrotizing enterocolitis in four of six recipients. Some immunosuppressive regimens gave modest graft survival, none resulted in indefinite graft survival, and there was considerable toxicity with many of the regimens. Although CS administration alone or in combination with irradiation resulted in modest pancreatic allograft survival in this model, the place of CS combined with TBI or TLI or other chemical immunosuppressive agents remains to be defined.

Prolongation of intraperitoneal segmental pancreatic allografts in primates receiving cyclosporin A

In this study the efficacy of the new immunosuppressive agent, cyclosporin A (CYA), was examined in a model of segmental, intraperitoneal pancreatic allotransplantation with free duct drainage in totally pancreatectomized, outbred Chacma baboons. CYA, in doses of 25 to 50 mg/kg/day administered to recipients of heterotopic segmental (tail) allografts, produced a slight but significant prolongation of graft survival. CYA (25 to 85 mg/kg/day), administered orally after pancreatic transplantation gave daily serum trough levels of CYA that ranged from 300 to 600 ng/ml. Mean serum trough levels on the first postoperative day in recipients of 50 mg/kg/day were 121.1 +/- 61.6 ng/ml. There was a wide variation in daily serum trough levels exhibited between primates on the same daily oral dose, and there was no correlation between absolute serum trough levels of CYA and rejection. It is postulated that adequate serum CYA levels were not achieved by the oral administration of the drug to ensure allograft survival beyond 60 days in pancreatectomized recipients. Adverse effects occurred frequently and included anorexia, diarrhea, and tremors and were in direct proportion to the quantity of CYA required to prolong graft survival. Free duct drainage into the abdominal cavity frequently resulted in pancreatic ascites, which necessitated paracentesis, indicating that this method of duct drainage has limited clinical application. Although heterotopic autotransplantation or allotransplantation of the tail of the pancreas in the baboon was capable of maintaining normoglycemia in pancreatectomized baboons, glucose intolerance, reduced K values, and hypoinsulinemia were consistent findings during glucose tolerance tests, suggesting that an insufficient islet cell mass had been transplanted.

Interstitial lung disease. Part I. A multidisciplinary approach to the diagnosis and assessment of disease activity

The value of alveolar lavage as an investigative technique was determined in patients with interstitial lung disease. Alveolar cytology was related to defined histopathological degrees of disease activity found in transbronchial biopsy specimens. The degree of disease activity as assessed by these two techniques was compared with radiological evaluation. Adequate specimens of lung tissue for histopathological evaluation were obtained by transbronchial biopsy in 95% of the subjects during the first procedure and diagnostic histopathological changes were found in 60% of the patients. In the evaluation of disease activity, the lymphocyte-macrophage (L-M) ratio and, to a lesser extent, the total alveolar cell counts correlated well with graded histopathological changes of activity. A graded radiological evaluation of activity was accurate in 14 out of 17 patients, but in 3, extreme cellular disease ws not recognized. Alveolar cytological examination can be employed as a supplement to the biopsy technique for increased accuracy in the initial and follow-up evaluation of active interstitial lung disease. An approach combining transbronchial biopsy, alveolar lavage and radiography, provides a safe and accurate alternative to openlung biopsy in most patients for determining the aetiology and degree of activity of interstitial lung disease.

Urinary porphyrins and porphyrin precursors in normal pregnancy. Relationship to urinary total oestrogen excretion,

The relationship between urinary excretion of porphyrins, porphyrin precursors and total oestrogens in normal pregnancy was investigated. Significant increases in total oestrogen, delta-aminolaevulinic acid (ALA) and coproporphyrin (COPRO) excretion were noted. However, no close correlation was found between total oestrogen excretion and urinary output of ALA and COPRO. The results suggest that the observed increases in ALA and COPRO excretion during pregnancy may not simply be the result of steroid-mediated induction of hepatic haem biosynthesis, as has been proposed.